I've never seen any Moorcock characters in EPU works. I don't know if Gryphon never read any, or just doesn't care for the author, but I've always thought there was a certain parallel between the way Moorcock eventually amalgamated every character and setting he'd published into one all-encompassing multiverse and the crossover extravaganza that is UF.

Sure, Elric is kind of twee, but John Daker/Erekose seems like he'd be oddly appropriate presence in UF. He's a bit of a dick, so I can readily imagine Utena giving him a thorough tongue-lashing. He'd have no choice but to accept the rebuke, as he'd be certain to recognize her as being a particularly noble (and sane) aspect of the Eternal Champion.